Delivery device, especially for colours and paints

Abstract: The present invention relates to a delivery device, especially for colours and paints, of the kind comprising a plurality of nozzles (1) or delivery ducts, said ducts being each connected to their own tank and arranged in such a way as to discharge into a single chamber (3) which is directed into an underlying container, characterized in that around the discharge nozzles a sealed chamber (4) with removable bottom is provided.

Description: The present invention relates to a delivery device, especially for colours and paints. From Italian patent 1.101.064 and Italian patent 0.215.555, of the same applicant, delivery devices for the same application are known. Said delivery devices comprise a plurality of nozzles, which are usually radially arranged, said nozzles being each connected to their own colour tank. The colour delivered from the nozzles falls into an underlying container, which is typically a can. When a colour flow is interrupted, in the nozzle or delivery duct there will almost always remain a certain amount of said colour. The liquid phase of the colour is prone to evaporate as it is in contact with the atmosphere, thereby causing the colour to dry up and the delivery duct to clog. The currently known delivery devices, especially for colours and paints, require consequently frequent troublesome maintenance operations. The specific object of the present invention is to overcome the above-mentioned draw-backs and find a delivery device, especially for colours and paints, which allows the colour remaining in the delivery ducts during a flow interruption phases to remain unaltered. A further object of the present invention is to provide a delivery device of a simple, low-cost construction. The above and other objects are achieved in a delivery device, especially for colours and paints, of the kind comprising a plurality of nozzles, or delivery ducts, characterized in that it comprises, around the discharge nozzles, a tight-sealed chamber with removable bottom. Further features and advantages of the invention will be more clearly understood from the description of a preferred, but not exclusive, embodiment of the delivery device, especially for colours and paints, which is illustratively shown in the accompanying drawing, in which figure 1 is a side elevation view, partly in section, of the device in stand-by condition, which embodiment must not be construed as limiting. With reference to the sole figure, the device comprises a plurality of discharge nozzles, or ducts, 1 for delivering the colour that is contained within tanks 2. Said nozzles are radially arranged and discharge into a tight-sealed chamber 3 which is closed in the lower part by a removable bottom 4 and in the upper part by a cover 5, said cover 5 being located over the array of nozzles 1. The side wall of the chamber consists of a flange 7 which is located under the array of nozzles 1, and a gasket 6, said gasket comprising two parts superposed to one another and being constrained between cover 5 and flange 7, so as to tighten, under deformation, the array of nozzles 1. Cover 5 is mounted on two or several screws or threaded spindles 8 with the interposition of springs 9 that try to rise the cover and remove it from the plan on which flange 7 rests, thereby separating the two parts that form gasket 6. Thus it is possible to raise cover 5 for a distance that is enough to remove one or several nozzles for maintenance operations, without the chamber having to be dismantled. The removable bottom 4 of tight-sealed chamber 3 preferably comprises on the inner side a cavity 15 which is filled with a sponge 16, said sponge being soaked in the same liquid that forms the liquid phase of the colour. When the tight-sealed chamber is closed, the liquid in which the sponge is soaked evaporates until an equilibrium with the vapour pressure of the liquid contained in the colour is reached. The tight-sealed chamber 3 provides therefore a controlled atmosphere which warrants that the colour remaining in the nozzles can not be deteriorated. The removable bottom 4 should conveniently be controlled by a linear actuator 20 which, through a kinematic motion system system 21, causes stopper 4 to be drawn to and removed from the lower part of flange 7. Said kinematic motion system 21 comprises a rod 23 of a linear actuator 20 which is hinged in 25 and moves rod 23, said rod being connected to a wedge-like support 27 to which the bottom part or lower closing stopper 4 of tight-sealed chamber 3 is fixed. The lower surface 26 of wedge 27 rests on a sphere 29 which is mounted on a support 30 and biased upward by a spring 31, thereby pushing with a controlled force the stopper 4 against the bottom part of chamber 3. On the upper surface 28 of wedge 27 there is fixed the stopper 4 that closes the tight-sealed chamber 3. In stand-by conditions, the delivery device shows the tight-sealed chamber 3, that is the stopper 4, pressed against flange 7. The stopper 4 is preferably made of a material exhibiting a certain elasticity so as to warrant a good seal on the flange. Before the colour delivery is resumed, the stopper 4 is removed by actuating the kinematic motion system 21. The opening/closing kinematic motion system of tight-sealed chamber 3 works as follows: the linear actuator 20 acts onto rod 23 drawing it back, which consequently draws-back wedge 27 on which the stopper 4 is fixed. The linear actuator 20 is hinged in 25, thereby possibly rotating and allowing the wedge 27 to be lowered while it is drawn back. The lower surface 26 of wedge 27 slides on sphere 29, which can freely rotate in its seat, which solution allows a low friction coefficient to be obtained. When the device has completed the colour delivery, chamber 3 is closed by inverting the operation sequence described above. In case of failure or misoperation within the tight-sealed chamber, it is enough to unscrew screws 8 for the springs 9 to raise cover 5 thereby separating the two parts of gaskets 6 and allowing are one or more nozzles to be removed without the need of troublesome removal operations of said cover. In practice of the invention, any materials can be employed and the dimensions can be chosen according to the needs.

Claims: A delivery device, especially for colours and paints, comprising a plurality of nozzles or delivery ducts (1), said ducts or nozzles being each connected to their own tank (2) and arranged in such a way as to discharge into a single chamber (3) which is directed into an underlying container, characterized in that around the discharge nozzles or ducts a tight-sealed chamber (3) with removable bottom (4) is provided. A device as claimed in claim 1, characterized in that within said tight-sealed chamber (3) a certain amount of liquid is provided which upon evaporation produces an equilibrium with the vapour pressure of the same liquid present in the colour. A device as claimed in claim 2, characterized in that on the inner side of said removable bottom part of said tight-sealed chamber a cavity (15) is provided containing a sponge (16) which is soaked in the liquid that is used to control the atmosphere of the tight-sealed chamber. A device as claimed in claim 1, characterized in that said tight-sealed chamber (3) comprises: a cover (5) located over the array of nozzles; a flange (7) located under the array of nozzles; a gasket (6) consisting of two superposed parts and radially crossed by the array of nozzles, said gasket being constrained between the cover and flange, so as to tighten, under the deformation, the array of nozzles; a plurality of screws (8) for tightening the cover to the flange. A device as claimed in claim 4, characterized in that on at least two screws elastic means are present, said elastic means (9) tending to raise the cover removing it from the plane on which the flange rests. A device as claimed in claim 1, characterized in that the removable bottom part (4) of the tight-sealed chamber is controlled by a kinematic motion system (21), said kinematic motion system (21) comprising: a linear actuator (20), said linear actuator possibly pivoting around an axis that is perpendicular to the translation direction of said linear actuator and perpendicular to the weight direction of said linear actuator; a wedge (27) on the upper surface (28) of which a stopper (4) is fixed, said wedge being directly connected to said linear actuator; fixed abutment means on which said wedge moves. A device as claimed in claim 6, characterized in that said fixed abutment means on which the wedge is moved comprise: a sphere (29) on which said wedge slides. A device as claimed in claim 6, characterized in that elastic means (31) are provided for setting the pressure the stopper applies to the flange of the tight-sealed chamber. A device as claimed in claim 7 and 8, characterized in that said elastic means for setting the pressure the stopper applies against the flange consist of a spring that biases said sphere against the lower surface (26) of the wedge. A device as claimed in claim 6, characterized in that said linear actuator is an air piston. A machine for the delivery of paints or colours, comprising a delivery device as claimed in the preceding claims.

Inventors: SINDONI GIUSEPPE, SINDONI, GIUSEPPE
Applicants: ITALTINTO SRL, ITALTINTO S.R.L.
Application year: 1994
Main classification: B01F13
IPC codes: B01F13